Three-dimensional fracture continuum characterization aided by surface time-domain electromagnetics and hydrogeophysical joint inversion—proof-of-concept

Abstract

Efficient and safe production of hydraulically fractured reservoirs benefits from the prediction of their geometrical attributes. Geophysical methods have the potential to provide data that is sensitive to fracture geometries, alleviating the typically sparse nature of in situ reservoir observations. Moreover, surface-based methods can be logistically and economically attractive since they avoid operational interference with the injection-well infrastructure. This contribution investigates the potential of the surface-based timedomain electromagnetic (EM) method. EM methods can play an important role owing to their sensitivity to injection-induced fluid property changes. Two other advantageous factors are the EM signal-enhancing effect of vertical steelcased wells and the fact that injected proppants can be enhanced to produce a stronger electrical conductivity contrast with the reservoir's connate fluid. Nevertheless, an optimal fracture characterization will no doubt require the integration of EM and reservoir injection and production data. We hence carry out our investigations within a hydrogeophysical parameter estimation framework where EM data and injection flow-rates are combined in a fully coupled way. Given the interdisciplinary nature of coupled hydrogeophysical inverse modeling, we dedicate one section to laying out key aspects in a didactic manner.

Advancing measurements and representations of subsurface heterogeneity and dynamic processes: towards 4D hydrogeology

“…More generally, cloud computing combined with increasing computational power is one avenue to allow modeling the subsurface at a higher 4D resolution for an increasing number of applications in the future (Hayley, 2017;Kurtz et al, 2017). The ongoing efforts for coupling different simulators, both in hydrogeology and hydrogeophysics, will also favor the incorporation of larger, more informative data sets (e.g., Commer et al, 2020). The incorporation of geophysical data, especially at the large scale, has remained limited for a long time by the use of empirical and local petrophysical relationship (Rubin and Hubbard, 2005).…”

Advancing measurements and representations of subsurface heterogeneity and dynamic processes: towards 4D hydrogeology

“…Cloud computing combined with increasing computational power should allow to model the subsurface at a higher 4D resolution for an increasing number of applications in the future, including for (small) consulting companies and field practitioners (Hayley, 2017;Kurtz et al, 2017). The ongoing efforts for coupling different simulators, both in hydrogeology and hydrogeophysics will also favor the incorporation of larger, more informative data sets in modelling efforts (e.g., Commer et al, 2020). .…”

Guest Editorial to the CouFrac 2018 Special Issue Coupled Thermal-Hydro-Mechanical-Chemical Processes in Fractured Media: Microscale to Macroscale Numerical Modeling

“…The study of Commer et al [10] investigates the potential of the surface-based time-domain electromagnetic (EM) method. They carried out investigations within a hydrogeophysical parameter estimation framework in which EM data and injection flow rates are combined in a fully coupled way.…”